--- loncom/auth/lonacc.pm	2016/02/20 00:12:49	1.163
+++ loncom/auth/lonacc.pm	2020/09/28 00:10:27	1.179
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Cookie Based Access Handler
 #
-# $Id: lonacc.pm,v 1.163 2016/02/20 00:12:49 raeburn Exp $
+# $Id: lonacc.pm,v 1.179 2020/09/28 00:10:27 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -102,6 +102,7 @@ use Apache::loncommon();
 use Apache::lonlocal;
 use Apache::restrictedaccess();
 use Apache::blockedaccess();
+use Apache::lonprotected();
 use Fcntl qw(:flock);
 use LONCAPA qw(:DEFAULT :match);
 
@@ -159,7 +160,7 @@ sub get_posted_cgi {
                         if (length($value) == 1) {
                             $value=~s/[\r\n]$//;
                         }
-                    } elsif ($fname =~ /\.(xls|doc|ppt)x$/i) {
+                    } elsif ($fname =~ /\.(xls|doc|ppt)(x|m)$/i) {
                         $value=~s/[\r\n]$//;
                     }
                     if (ref($fields) eq 'ARRAY') {
@@ -289,7 +290,6 @@ sub upload_size_allowed {
 sub sso_login {
     my ($r,$handle,$username) = @_;
 
-    my $lonidsdir=$r->dir_config('lonIDsDir');
     if (($r->user eq '') || ($username ne '') || ($r->user eq 'public:public') ||
         (defined($env{'user.name'}) && (defined($env{'user.domain'}))
 	  && ($handle ne ''))) {
@@ -339,13 +339,39 @@ sub sso_login {
         }
         unless ($hosthere) {
             ($is_balancer,$otherserver) =
-                &Apache::lonnet::check_loadbalancing($user,$domain);
+                &Apache::lonnet::check_loadbalancing($user,$domain,'login');
+            if ($is_balancer) {
+                # Check if browser sent a LON-CAPA load balancer cookie (and this is a balancer)
+                my ($found_server,$balancer_cookie) = &Apache::lonnet::check_for_balancer_cookie($r);
+                if (($found_server) && ($balancer_cookie =~ /^\Q$domain\E_\Q$user\E_/)) {
+                    $otherserver = $found_server;
+                } elsif ($otherserver eq '') {
+                    my $lowest_load;
+                    ($otherserver,undef,undef,undef,$lowest_load) = &Apache::lonnet::choose_server($domain);
+                    if ($lowest_load > 100) {
+                        $otherserver = &Apache::lonnet::spareserver($lowest_load,$lowest_load,1,$domain);
+                    }
+                    if ($otherserver ne '') {
+                        my @hosts = &Apache::lonnet::current_machine_ids();
+                        if (grep(/^\Q$otherserver\E$/,@hosts)) {
+                            $hosthere = $otherserver;
+                        }
+                    }
+                }
+            }
         }
-
-	if ($is_balancer) {
+	if (($is_balancer) && (!$hosthere)) {
 	    # login but immediately go to switch server to find us a new 
 	    # machine
 	    &Apache::lonauth::success($r,$user,$domain,$home,'noredirect');
+            foreach my $item (keys(%form)) {
+                $env{'form.'.$item} = $form{$item};
+            }
+            unless ($form{'symb'}) {
+                unless (($r->uri eq '/adm/roles') || ($r->uri eq '/adm/sso')) {
+                    $env{'form.origurl'} = $r->uri;
+                }
+            }
             $env{'request.sso.login'} = 1;
             if (defined($r->dir_config("lonSSOReloginServer"))) {
                 $env{'request.sso.reloginserver'} =
@@ -360,14 +386,7 @@ sub sso_login {
 	} else {
 	    # need to login them in, so generate the need data that
 	    # migrate expects to do login
-	    my $ip;
-	    my $c = $r->connection;
-	    eval {
-	        $ip = $c->remote_ip();
-	    };
-	    if ($@) {
-	        $ip = $c->client_ip();
-	    }
+	    my $ip = $r->get_remote_host();
 	    my %info=('ip'        => $ip,
 		      'domain'    => $domain,
 		      'username'  => $user,
@@ -391,6 +410,9 @@ sub sso_login {
                 $info{'sso.reloginserver'} = 
                     $r->dir_config('lonSSOReloginServer'); 
             }
+            if (($is_balancer) && ($hosthere)) {
+                $info{'noloadbalance'} = $hosthere;
+            }
 	    my $token = 
 		&Apache::lonnet::tmpput(\%info,
 					$r->dir_config('lonHostID'));
@@ -430,6 +452,22 @@ sub sso_login {
     return undef;
 }
 
+sub needs_symb_check {
+    my ($requrl) = @_;
+    $requrl=~/\.(\w+)$/;
+    if ((&Apache::loncommon::fileembstyle($1) eq 'ssi') ||
+        ($requrl=~/^\/adm\/.*\/(aboutme|smppg|bulletinboard)(\?|$ )/x) ||
+        ($requrl=~/^\/adm\/wrapper\//) ||
+        ($requrl=~m|^/adm/coursedocs/showdoc/|) ||
+        ($requrl=~m|\.problem/smpedit$|) ||
+        ($requrl=~/^\/public\/.*\/syllabus$/) ||
+        ($requrl=~/^\/adm\/(viewclasslist|navmaps)$/) ||
+        ($requrl=~/^\/adm\/.*\/aboutme\/portfolio(\?|$)/)) {
+        return 1;
+    }
+    return;
+}
+
 sub handler {
     my $r = shift;
     my $requrl=$r->uri;
@@ -496,7 +534,7 @@ sub handler {
                 my $preserved;
                 foreach my $pair (split(/&/,$query)) {
                     my ($name, $value) = split(/=/,$pair);
-                    unless ($name eq 'symb') {
+                    unless (($name eq 'symb') || ($name eq 'usehttp')) {
                         $preserved .= $pair.'&';
                     }
                     if (($env{'request.course.id'}) && ($name eq 'folderpath')) {
@@ -515,7 +553,8 @@ sub handler {
             }
         } elsif ($env{'request.course.id'} &&
                  (($requrl =~ m{^/adm/$match_domain/$match_username/aboutme$}) ||
-                  ($requrl =~ m{^/public/$cdom/$cnum/syllabus$}))) {
+                  ($requrl eq "/public/$cdom/$cnum/syllabus") ||
+                  ($requrl =~ m{^/adm/$cdom/$cnum/\d+/ext\.tool$}))) {
             my $query = $r->args;
             if ($query) {
                 foreach my $pair (split(/&/,$query)) {
@@ -536,6 +575,7 @@ sub handler {
             my $lonhost = &Apache::lonnet::host_from_dns($hostname);
             if ($lonhost) {
                 my $actual = &Apache::lonnet::absolute_url($hostname);
+                my $exphostname = &Apache::lonnet::hostname($lonhost);
                 my $expected = $Apache::lonnet::protocol{$lonhost}.'://'.$hostname;
                 unless ($actual eq $expected) {
                     $env{'request.use_absolute'} = $expected;
@@ -551,7 +591,7 @@ sub handler {
         my $checkexempt;
         if ($env{'user.loadbalexempt'} eq $r->dir_config('lonHostID')) {
             if ($env{'user.loadbalcheck.time'} + 600 > time) {
-                $checkexempt = 1;    
+                $checkexempt = 1;
             }
         }
         if ($env{'user.noloadbalance'} eq $r->dir_config('lonHostID')) {
@@ -561,24 +601,73 @@ sub handler {
             ($is_balancer,$otherserver) =
                 &Apache::lonnet::check_loadbalancing($env{'user.name'},
                                                      $env{'user.domain'});
+            if ($is_balancer) {
+                unless (($requrl eq '/adm/switchserver') && (!$r->is_initial_req())) {
+                    # Check if browser sent a LON-CAPA load balancer cookie (and this is a balancer)
+                    my ($found_server,$balancer_cookie) = &Apache::lonnet::check_for_balancer_cookie($r);
+                    if (($found_server) && ($balancer_cookie =~ /^\Q$env{'user.domain'}\E_\Q$env{'user.name'}\E_/)) {
+                        $otherserver = $found_server;
+                    }
+                }
+            }
         }
         if ($is_balancer) {
-            $r->set_handlers('PerlResponseHandler'=>
-                             [\&Apache::switchserver::handler]);
-            if ($otherserver ne '') {
-                $env{'form.otherserver'} = $otherserver;
+            unless (($requrl eq '/adm/switchserver') && (!$r->is_initial_req())) {
+                $r->set_handlers('PerlResponseHandler'=>
+                                 [\&Apache::switchserver::handler]);
+                if ($otherserver ne '') {
+                    $env{'form.otherserver'} = $otherserver;
+                }
             }
             unless (($env{'form.origurl'}) || ($r->uri eq '/adm/roles') ||
                     ($r->uri eq '/adm/switchserver') || ($r->uri eq '/adm/sso')) {
                 $env{'form.origurl'} = $r->uri;
             }
         }
-
+        if ($requrl=~m{^/+tiny/+$match_domain/+\w+$}) {
+            if ($env{'user.name'} eq 'public' &&
+                $env{'user.domain'} eq 'public') {
+                $env{'request.firsturl'}=$requrl;
+                return FORBIDDEN;
+            } else {
+                return OK;
+            }
+        }
 # ---------------------------------------------------------------- Check access
 	my $now = time;
-	if ($requrl !~ m{^/(?:adm|public|prtspool)/}
+	if ($requrl !~ m{^/(?:adm|public|(?:prt|zip)spool)/}
 	    || $requrl =~ /^\/adm\/.*\/(smppg|bulletinboard)(\?|$ )/x) {
-	    my $access=&Apache::lonnet::allowed('bre',$requrl);
+            my ($access,$poss_symb);
+            if (($env{'request.course.id'}) && (!$suppext) && (&needs_symb_check($requrl))) {
+                unless ($env{'form.symb'}) {
+                    if ($r->args) {
+                        &Apache::loncommon::get_unprocessed_cgi($r->args,['symb']);
+                    }
+                }
+                if ($env{'form.symb'}) {
+                    $poss_symb=&Apache::lonnet::symbclean($env{'form.symb'});
+                }
+                if ($poss_symb) {
+                    my ($possmap,$resid,$url)=&Apache::lonnet::decode_symb($poss_symb);
+                    $url = &Apache::lonnet::clutter($url);
+                    unless (($url eq $requrl) && (&Apache::lonnet::is_on_map($possmap))) {
+                        undef($poss_symb);
+                    }
+                    if ($poss_symb) {
+                        if ((!$env{'request.role.adv'}) && ($env{'acc.randomout'}) &&
+                            ($env{'acc.randomout'}=~/\&\Q$poss_symb\E\&/)) {
+                            undef($poss_symb);
+                        }
+                    }
+                }
+                if ($poss_symb) {
+                    $access=&Apache::lonnet::allowed('bre',$requrl,$poss_symb);
+                } else {
+                    $access=&Apache::lonnet::allowed('bre',$requrl,'','','','',1);
+                }
+            } else {
+                $access=&Apache::lonnet::allowed('bre',$requrl);
+            }
             if ($handle eq '') {
                 unless ($access eq 'F') {
                     if ($requrl =~ m{^/res/$match_domain/$match_username/}) {
@@ -595,9 +684,21 @@ sub handler {
 		return OK;
 	    }
             if ($access eq 'B') {
+                if ($poss_symb) {
+                    if ($requrl=~m{^(/adm/.*/aboutme)/portfolio$}) {
+                        $requrl = $1;
+                    }
+                    if (&Apache::lonnet::symbverify($poss_symb,$requrl)) {
+                        $env{'request.symb'} = $poss_symb;
+                    }
+                }
                 &Apache::blockedaccess::setup_handler($r);
                 return OK;
             }
+            if ($access eq 'D') {
+                &Apache::lonprotected::setup_handler($r);
+                return OK;
+            }
 	    if (($access ne '2') && ($access ne 'F')) {
                 if ($requrl =~ m{^/res/}) {
                     $access = &Apache::lonnet::allowed('bro',$requrl);
@@ -654,16 +755,8 @@ sub handler {
 # ------------------------------------------------------------- This is allowed
 	if ($env{'request.course.id'}) {
 	    &Apache::lonnet::countacc($requrl);
-	    $requrl=~/\.(\w+)$/;
             my $query=$r->args;
-	    if ((&Apache::loncommon::fileembstyle($1) eq 'ssi') ||
-		($requrl=~/^\/adm\/.*\/(aboutme|smppg|bulletinboard)(\?|$ )/x) ||
-		($requrl=~/^\/adm\/wrapper\//) ||
-		($requrl=~m|^/adm/coursedocs/showdoc/|) ||
-		($requrl=~m|\.problem/smpedit$|) ||
-		($requrl=~/^\/public\/.*\/syllabus$/) ||
-                ($requrl=~/^\/adm\/(viewclasslist|navmaps)$/) ||
-                ($requrl=~/^\/adm\/.*\/aboutme\/portfolio(\?|$)/)) {
+            if (&needs_symb_check($requrl)) {
 # ------------------------------------- This is serious stuff, get symb and log
 		my $symb;
 		if ($query) {
@@ -671,9 +764,16 @@ sub handler {
 		}
 		if ($env{'form.symb'}) {
 		    $symb=&Apache::lonnet::symbclean($env{'form.symb'});
-		    if ($requrl =~ m|^/adm/wrapper/|
+		    if ($requrl eq '/adm/navmaps') {
+                        my ($map,$mid,$murl)=&Apache::lonnet::decode_symb($symb);
+                        &Apache::lonnet::symblist($map,$murl => [$murl,$mid]);
+		    } elsif ($requrl =~ m|^/adm/wrapper/|
 			|| $requrl =~ m|^/adm/coursedocs/showdoc/|) {
 			my ($map,$mid,$murl)=&Apache::lonnet::decode_symb($symb);
+                        if ($map =~ /\.page$/) {
+                            my $mapsymb = &Apache::lonnet::symbread($map);
+                            ($map,$mid,$murl)=&Apache::lonnet::decode_symb($mapsymb); 
+                        }
 			&Apache::lonnet::symblist($map,$murl => [$murl,$mid],
 						  'last_known' =>[$murl,$mid]);
 		    } elsif ((&Apache::lonnet::symbverify($symb,$requrl)) ||
@@ -682,6 +782,10 @@ sub handler {
                              (($requrl=~m|(.*/aboutme)/portfolio$|) &&
                               &Apache::lonnet::symbverify($symb,$1))) {
 			my ($map,$mid,$murl)=&Apache::lonnet::decode_symb($symb);
+                        if (($map =~ /\.page$/) && ($requrl !~ /\.page$/)) {
+                            my $mapsymb = &Apache::lonnet::symbread($map);
+                            ($map,$mid,$murl)=&Apache::lonnet::decode_symb($mapsymb);
+                        }
 			&Apache::lonnet::symblist($map,$murl => [$murl,$mid],
 						  'last_known' =>[$murl,$mid]);
 		    } else {
@@ -697,22 +801,58 @@ sub handler {
                     }
                     unless ($suppext) {
 		        $symb=&Apache::lonnet::symbread($requrl);
-		        if (&Apache::lonnet::is_on_map($requrl) && $symb &&
-			    !&Apache::lonnet::symbverify($symb,$requrl)) {
-			    $r->log_reason('Invalid symb for '.$requrl.': '.$symb);
-			    $env{'user.error.msg'}=
-			        "$requrl:bre:1:1:Invalid Access";
-			    return HTTP_NOT_ACCEPTABLE; 
-		        }
+                        if (&Apache::lonnet::is_on_map($requrl) && $symb) {
+                            my ($encstate,$invalidsymb);
+                            unless (&Apache::lonnet::symbverify($symb,$requrl,\$encstate)) {
+                                $invalidsymb = 1;
+                                #
+                                # If $env{'request.enc'} is true, but no encryption for $symb retrieved
+                                # by original lonnet::symbread() call, call again to check for an instance
+                                # of $requrl in the course which has encryption, and set that as the symb.
+                                # If there is no such symb, or symbverify() fails for the new symb proceed
+                                # to report invalid symb.
+                                #
+                                if ($env{'request.enc'} && !$encstate) {
+                                    my %possibles;
+                                    my $nocache = 1;
+                                    $symb = &Apache::lonnet::symbread($requrl,'','','',\%possibles,$nocache);
+                                    if ($symb) {
+                                        if (&Apache::lonnet::symbverify($symb,$requrl)) {
+                                            $invalidsymb = '';
+                                        }
+                                    } elsif (keys(%possibles) > 1) {
+                                        $r->internal_redirect('/adm/ambiguous');
+                                        return OK;
+                                    }
+                                }
+                                if ($invalidsymb) {
+                                    $r->log_reason('Invalid symb for '.$requrl.': '.$symb);
+                                    $env{'user.error.msg'}=
+                                        "$requrl:bre:1:1:Invalid Access";
+                                    return HTTP_NOT_ACCEPTABLE;
+                                }
+                            }
+                        }
 		        if ($symb) {
 			    my ($map,$mid,$murl)=
 			        &Apache::lonnet::decode_symb($symb);
-			    &Apache::lonnet::symblist($map,$murl =>[$murl,$mid],
-						      'last_known' =>[$murl,$mid]);
+                            if ($requrl eq '/adm/navmaps') {
+                                &Apache::lonnet::symblist($map,$murl =>[$murl,$mid]);
+                            } else {
+                                if (($map =~ /\.page$/) && ($requrl !~ /\.page$/)) {
+                                    my $mapsymb = &Apache::lonnet::symbread($map);
+                                    ($map,$mid,$murl)=&Apache::lonnet::decode_symb($mapsymb);
+                                }
+			        &Apache::lonnet::symblist($map,$murl =>[$murl,$mid],
+						          'last_known' =>[$murl,$mid]);
+                            }
 		        }
 		    }
 		}
 		$env{'request.symb'}=$symb;
+                if (($env{'request.symbread.cached.'}) && ($env{'request.symbread.cached.'} ne $symb)) {
+                    $env{'request.symbread.cached.'} = $symb;
+                }
 		&Apache::lonnet::courseacclog($symb);
 	    } else {
 # ------------------------------------------------------- This is other content